Multiple system atrophy

Multiple system atrophy (MSA) is a rare neurodegenerative disorder characterized by autonomic dysfunction, tremors, slow movement, muscle rigidity, and postural instability (collectively known as parkinsonism) and ataxia. This is caused by progressive degeneration of neurons in several parts of the brain including the basal ganglia, inferior olivary nucleus, and cerebellum. Many people affected by MSA experience dysfunction of the autonomic nervous system, which commonly manifests as orthostatic hypotension, impotence, loss of sweating, dry mouth and urinary retention and incontinence. Palsy of the vocal cords is an important and sometimes initial clinical manifestation of the disorder. A modified form of the alpha-synuclein protein within affected neurons may cause MSA. About 55% of MSA cases occur in men, with those affected first showing symptoms at the age of 50–60 years. MSA often presents with some of the same symptoms as Parkinson's disease. However, those with MSA generally show little response to the dopamine medications used to treat Parkinson's disease and only about 9% of MSA patients with tremor exhibit a true parkinsonian pill-rolling tremor. MSA is distinct from multisystem proteinopathy, a more common muscle-wasting syndrome. MSA is also different from multiple organ dysfunction syndrome, sometimes referred to as multiple organ failure, and from multiple organ system failures, an often-fatal complication of septic shock and other severe illnesses or injuries. MSA is characterized by the following, which can be present in any combination: autonomic dysfunction parkinsonism (muscle rigidity +/ tremor and slow movement) cerebellar ataxia (Poor coordination/unsteady walking, double vision) A variant with combined features of MSA and dementia with Lewy bodies may also exist. There have also been occasional instances of frontotemporal lobar degeneration associated with MSA. The most common first sign of MSA is the appearance of an "akinetic-rigid syndrome" (i.e.